General Questions

GENERAL QUESTIONS

Cells

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Animals, Animals, plants, plants, fungi, fungi, and protists are eukaryotes. eukaryotes. In these organisms the genetical material is organized into a nucleus.

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Prokaryotes (bacteria and Archaea) rchaea) don’ don’t have their genetic material into a nucleus.

B.K.Kolita Kamal Jinadasa, Jinadasa, Post Harvest Technology Division, NARA, ColomboColombo-15, Sri Lanka. Eukaryote cell

Prokaryote cell

Structures of a cell (in general) „

Cells contained some organelles:

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Plasmatic membrane : The cell membrane surrounds the cytoplasm of a cell and physically separates the intracellular components from the extracellular environment. This barrier is able to regulate what enters. It contains a variety of biological molecules, molecules, primarily proteins and lipids, lipids, which are involved in a vast array of cellular processes.

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Mitochondria: Mitochondria: it’ it’s a membranemembrane-enclosed organelle. organelle. A mitochondrion contains inner and outer membranes composed of phospholipid bilayers and proteins. proteins. A dominant role for the mitochondria is the production of ATP. ATP. It contains DNA.

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Vacuoles are membranemembrane-bound compartments within some eukaryotic cells that can serve a variety of secretory, secretory, excretory, and storage function.

4.

Golgi apparatus. apparatus. The primary function of the Golgi apparatus is to process and package macromolecules synthesised by the cell, primarily proteins and lipids. lipids.

Organelles „

The endoplasmic reticulum or ER is an interconnected network of tubules, tubules, vesicles and cisternae that is responsible for several specialized functions: Protein translation, translation, folding, and transport of proteins to be used in the cell membrane. membrane.

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A ribosome is a small, dense collection of rRNA and proteins that assembles proteins. proteins. Ribosomes consist of two subunits (Figure 1) that fit together (Figure 2) and work as one to translate the mRNA into a polypeptide chain during protein synthesis.

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the nucleus is a membranemembrane-enclosed organelle found in most eukaryotic cells. cells. It contains most of the cell's genetic material. material. Here stay the nucleic acids. acids.

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Prokaryotes don’ don’t have nucleus and contain a single loop of DNA stored in an area area named the nucleoid. nucleoid.

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A plasmid is a DNA molecule separate from the chromosomal DNA and capable of autonomous replication. It is typically circular and doubledouble-stranded. It usually occurs in bacteria. bacteria.

Cell membrane

Mitochondria

Ribosome and endoplasmatic rethiculum. rethiculum. Ribosome

Endoplasmatic reticulum

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